WATFORD CITY (AP) - Nineteen bighorn sheep from Montana appear to be doing well after their release into an area of the Badlands near the north unit of Theodore Roosevelt National Park, state officials say.

The additions bring North Dakota's bighorn sheep population to 250 along the Little Missouri River within the Badlands, Game and Fish Department officials say.

Bighorn sheep biologist Brett Wiedmann said the five rams and 14 ewes released Jan. 17 were captured at the Charles M. Russell National Wildlife Refuge along the Missouri River in north central Montana.

Helicopter crews used net guns to capture the sheep, and the animals were fitted with radio-transmitter collars and tested for brucellosis, he said.

After the sheep tested negative for brucellosis, he said, Game and Fish personnel hauled the bighorns in two large trailers to their new home in the Badlands.

The move took less than two days, he said.

"Typically, when you put bighorn sheep in the trailer, they calm down real well," he said. "They were in good health."

Wiedmann said four surveillance flights in the last week have shown the sheep are alive and staying in the transplant area. Typically, he said, the first week is crucial for bighorn sheep to survive the stress of capture.

The transplant, about a year in the planning, is a partnership between the state Game and Fish Department and the Minnesota-Wisconsin Chapter of the Foundation for North American Wild Sheep.

Wiedmann said the chapter pays the capture and testing costs, which run about $800 per animal, while the Game and Fish Department provides personnel and equipment for hauling the animals.

Wiedmann said the chapter has funded three out-of-state transplants and four in-state sheep transplants since 2003, and its support has been crucial to the success of North Dakota's bighorn sheep program.

Each March, the chapter auctions a North Dakota sheep license, raising thousands of dollars annually for bighorn research in the state.

"There's very little cost to the department," Wiedmann said.

"They have put thousands of dollars into our sheep program, and 99 percent of them will never hunt bighorn sheep in North Dakota. They do it just because they love wild sheep."

The Minnesota-Wisconsin chapter also has members from North Dakota, Wiedmann said.

Wiedmann said the Game and Fish Department's goal is a sustainable population of 300 sheep. Bighorns do best in small groups, he said, and North Dakota's population is dispersed among 15 herds.

"We're in a good situation in that we have a lot of habitat that doesn't have sheep right now in the Badlands," Wiedmann said. "The limiting factor in the past has been availability of sheep and funding."